Connector, structure, and flight body

Abstract

To provide a connector which connects three or more rods highly strongly, and which is lightweight.SOLUTION: A connector for connecting three or more rods all extending in a horizontal direction, includes: two end members and one or more middle members to which the rods are fitted one by one respectively; and auxiliary members. The end member includes: an end member body; an end through-hole which penetrates the end member body in a horizontal direction and to which the rod is inserted; a split groove which is formed in the end member body and allows communication between the end through-hole and an outside of the end member body; and fasteners for fastening the end member body so as to narrow a width of the split groove. The middle member includes: a middle member body; and a middle through-hole which penetrates the middle member body in the horizontal direction and through which the rod is inserted. The middle member is interposed between the two vertically positioned end members. The end member bodies and the middle member body are integrated. The auxiliary members are intended to fix the rod to the middle member body.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a connector for connecting rods, a structure including the connector and the rods, and an aircraft having the structure as its airframe. [Background technology]

[0002] In unmanned aerial vehicles (UAVs, drones, etc.), which have become widespread in recent years, the most commonly seen configuration is as shown in Figures 14 and 15 of Patent Document 1. That is, a fuselage having a control unit and a battery is located in the center, and multiple arms (six in the example of Patent Document 1) extend radially from the fuselage. The base end of each arm is fixed to the fuselage, and a rotor is attached to the tip.

[0003] Incidentally, in such unmanned aerial vehicles, it is important to reduce weight while maintaining the necessary strength in order to extend flight time (range) as much as possible with the limited battery capacity. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-6953 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the unmanned aerial vehicle of Patent Document 1, each arm was fixed to the fuselage by a fixing member, which required one fixing member for each arm, and the fuselage also had to be sufficiently strong, making it difficult to reduce weight.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a lightweight connector that can connect three or more rods with high strength, a structure that includes the connector and the rods, and an aircraft that uses the structure as its airframe. [Means for solving the problem]

[0007] The connector of the present invention is a connector for connecting three or more rods, all of which extend horizontally, and comprises two end members and one or more central members, to each of which one rod is attached, and an auxiliary member, wherein the end members have an end member body, an end through hole that penetrates the end member body horizontally and into which the rod is inserted, a split groove formed in the end member body connecting the end through hole to the outside of the end member body, and a fastener that tightens the end member body so as to narrow the width of the split groove, and the central member has a central member body and a central through hole that penetrates the central member body horizontally and into which the rod is inserted, the central member is sandwiched between two end members positioned above and below, and the end member body and the central member body are integrated, and the auxiliary member fixes the bar to the central member body. It should be noted that the "horizontally extending rod" and "the two end members positioned one above the other" are based on their respective states (postures) for the purpose of explanation, and they may be in different states when implementing the present invention.

[0008] Furthermore, the connecting device of the present invention may be one in which the auxiliary member is attached to the central member body, and includes an auxiliary member body, an auxiliary through hole that penetrates the auxiliary member body horizontally and into which the rod material is inserted, an auxiliary split groove formed in the auxiliary member body connecting the auxiliary through hole with the outside of the auxiliary member body, and an auxiliary fastener that tightens the auxiliary member body so as to narrow the width of the auxiliary split groove.

[0009] In the connector of the present invention, the auxiliary members may be attached to the respective surfaces of the inner member body where both ends of the inner through hole open.

[0010] Furthermore, the connector of the present invention may be a connector for connecting three of the rods, and may include one of the central members, with the directions in which the rods extend differing by 60 degrees when viewed from above.

[0011] The structure of the present invention is characterized in that it comprises the connecting device and the rod material, the rod material being inserted into the end through hole of the end member and fastened with the fastener to fix the rod material to the end member body, and the rod material being inserted into the center through hole of the central member and fixed to the central member body by the auxiliary member.

[0012] The flying body of the present invention is characterized in that the structure is an airframe, and rotors are provided at both ends of each of the rods. Effect of the Invention

[0013] According to the connector of the present invention, a structure can be constructed in which a plurality of rods extend horizontally from the connector. The rods penetrate the connector and can extend on both sides, so that the rods extend in a direction twice as long as the number of rods from the connector. The structure is such that the rods penetrate the end member body and the center member body, which are integrated, and are fixed, so that the structure is strong. In addition, the structure is such that each rod extends from one end of the structure to the other end without being cut, so that the structure is also strong. Furthermore, in the end member, the rods inserted into the end through holes are fastened and fixed with a fastener, so that the structure is particularly strong and easy to fix. In addition, since a plurality of rods can be connected with one connector, the structure is lightweight.

[0014] Furthermore, if the auxiliary member is a member that fastens the rod inserted into the auxiliary through hole by tightening it with an auxiliary fastener, the rod that passes through the central member that does not have a split groove can be fixed with high strength and easily.

[0015] Furthermore, if the auxiliary members are attached to both sides of the central member body, the bar can be more securely fixed to the central member compared to, for example, an auxiliary member that is attached to only one side of the central member body.

[0016] Furthermore, by connecting three rods whose extension directions differ by 60 degrees each when viewed from above, a structure can be formed in which the ends of each rod are positioned at the vertices of a regular hexagon when viewed from above.

[0017] The structure formed by the connector and rod of the present invention is strong and lightweight as described above. Such a strong and lightweight structure is suitable for the body of an aircraft and contributes to extending the flight time (range) of the aircraft. [Brief description of the drawings]

[0018] [Figure 1] FIG. 2 is a perspective view of the connector of the first embodiment. [Diagram 2] 1 shows an end member and a central member, where (a) is a top view, (b) is a front view, and (c) is a right side view. [Diagram 3] 1A, 1B, 1C, and 1D are a top view, a left side view, a front view, and a right side view, respectively, of the auxiliary member. [Figure 4] FIG. [Diagram 5] FIG. [Figure 6] FIG. 11 is a perspective view of a connector according to a second embodiment. [Figure 7] FIG. 11 is a perspective view of a connector according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] The specific contents of the connector of the present invention will be described below. In the first embodiment of this connector, three rods, all of which extend horizontally, are connected to form a structure. There are various uses for structures, but here we will show a case where the structure is used as the body of an aircraft. In the following, the front-rear, left-right, up-down directions are defined as the directions shown in FIG. 1. That is, in the connector 100, the direction in which the central through-hole 22 extends (horizontal direction) is defined as the front-rear direction, the direction perpendicular to the front-rear direction and horizontal is defined as the left-right direction, and the direction perpendicular to the front-rear direction and the left-right direction is defined as the up-down direction.

[0020] As shown in Fig. 1, the connector 100 includes two end members 10, one central member 20, and two auxiliary members 30. From the top, the end members 10, the central member 20, and the end members 10 are stacked in this order, and the two auxiliary members 30 are attached to the central member 20. As shown in Fig. 4, the rod material 200 to be connected is a pipe with a circular cross section. The rod material 200 is made of CFRP.

[0021] As shown in Figs. 1 and 2, two end members 10 are provided, one above the other, and have the same shape but different postures. Here, the upper end member 10 will be described. The end member 10 has an end member body 11, an end through hole 12 penetrating the end member body 11 and into which a bar 200 is inserted, a split groove 13 formed in the end member body 11 and connecting the end through hole 12 to the outside of the end member body 11, and a fastener 14 for tightening the end member body 11 so as to narrow the width of the split groove 13. The end member body 11 is made of an aluminum alloy. The end member body 11 is in the shape of a rectangular parallelepiped. More specifically, a pair of opposing faces of the end member body 11 are rectangular in shape with adjacent sides having slightly different lengths, and these two faces are called end faces 11a. The end face 11a is a vertical face, with the horizontal sides being the short sides and the vertical sides being the long sides. The four faces perpendicular to the end face 11a are rectangular, and the long sides are approximately twice as long as the short sides. These four faces are called side faces 11b. The direction in which the long sides of the side faces 11b extend is called the longitudinal direction of the end member body 11. The longitudinal direction is horizontal. The end through hole 12 penetrates the end member body 11 from one end face 11a to the other end face 11a. In other words, the end through hole 12 extends along the longitudinal direction of the end member body 11. The end through hole 12 has a circular cross section, and its diameter is large enough to fit the bar 200. The center of the end through hole 12 is slightly shifted downward (toward one of the short sides) from the center of the end face 11a. The split groove 13 is formed on the upper side face 11b of the end member body 11. The upper side surface 11b is the side surface 11b that contacts the other short side (the short side far from the end through hole 12) of the end surface 11a. The split groove 13 extends from the center of one short side of the side surface 11b to the center of the other short side along the longitudinal direction of the end member body 11. The split groove 13 penetrates in the vertical direction from the surface of the side surface 11b to the end through hole 12. In addition, four bolt holes 15 are formed in a row along the longitudinal direction at the upper end of one vertically oriented side surface 11b. The bolt holes 15 extend in the horizontal direction, penetrate the end member body 11, and open into the split groove 13. Furthermore, four female screw holes 16 are formed on the surface of the split groove 13 that faces the surface where each bolt hole 15 opens. The female screw holes 16 face the bolt holes 15, respectively. The female screw holes 16 extend in the horizontal direction and do not penetrate to the side surface 11b. The fastener 14 consists of four bolts.When the fastener 14 is inserted into the bolt hole 15, the tip of the fastener 14 screws into the female screw hole 16. By screwing the fastener 14 with its head engaged with the side surface 11b, the end member body 11 is tightened so as to narrow the width of the split groove 13. Therefore, when the fastener 14 is screwed into the end member body 11 with the bar 200 inserted into the end through hole 12, the bar 200 is tightened to the end member body 11 and fixed to the end member body 11. Female screw holes 17 are formed at the four corners of the end face 11a and at two locations along each long side of the upper side surface 11b. A circular communication hole 18 is formed in the center of the two vertically oriented side surfaces 11b, penetrating to the end through hole 12.

[0022] The central member 20 has a central member body 21 and a central through hole 22 that penetrates the central member body 21 and into which the bar 200 is inserted. The central member body 21 is made of an aluminum alloy. The central member body 21 is rectangular. More specifically, a pair of opposing faces of the central member body 21 is a square, and these two faces are called end faces 21a. The end faces 21a are vertical faces. Four faces perpendicular to the end faces 21a are rectangular, and the long sides are approximately twice as long as the short sides. These four faces are called side faces 21b. The direction in which the long sides of the side faces 21b extend is called the longitudinal direction of the central member body 21. The longitudinal direction is horizontal. The length of the side of the end face 21a is the same as the length of the short side of the end face 11a of the end member body 11. The length of the long side of the side face 21b is the same as the length of the long side of the side face 11b of the end member body 11. The central through hole 22 penetrates from one end face 21a of the central member body 21 to the other end face 21a. That is, the central through hole 22 extends along the longitudinal direction of the central member body 21. The central through hole 22 has a circular cross section, and its diameter is large enough to fit the bar 200. The center of the central through hole 22 coincides with the center of the end face 21a. Female screw holes 27 for attaching the auxiliary member 30 described below are formed in the four corners of the end face 21a. Circular communication holes 28 that penetrate to the central through hole 22 are formed in the centers of the two vertically oriented side faces 21b.

[0023] The middle member 20 is sandwiched between two end members 10 positioned above and below. That is, the shape is three rectangular parallelepipeds stacked on top of each other. The longitudinal direction of the middle member 20 coincides with the front-rear direction. The longitudinal direction of the upper end member 10 coincides with the direction rotated 60 degrees counterclockwise from the front-rear direction when viewed from above. The side surface 11b of the lower end member 10 on which the split groove 13 is formed is located on the lower side. The longitudinal direction of the lower end member 10 coincides with the direction rotated 60 degrees clockwise from the front-rear direction when viewed from above. That is, the end through holes 12 of the two end members 10 and the middle through hole 22 of the middle member 20 extend in directions that differ by 60 degrees. The lower side surface 11b of the upper end member 10 and the upper side surface 21b of the middle member 20 are in contact with each other, and the upper side surface 11b of the lower end member 10 and the lower side surface 21b of the middle member 20 are in contact with each other. The centers of the two end members 10 and the central member 20 are aligned in a top view, forming a regular hexagon in a top view. The two end member bodies 11 and the central member body 21 are integrally formed. In other words, they may be machined from a metal block or may be cast.

[0024] As shown in FIG. 1 and FIG. 3, the auxiliary member 30 fixes the bar 200 to the central member body 21. The auxiliary member 30 has an auxiliary member body 31, an auxiliary through hole 32 penetrating the auxiliary member body 31 and into which the bar 200 is inserted, an auxiliary split groove 33 formed in the auxiliary member body 31 and communicating between the auxiliary through hole 32 and the outside of the auxiliary member body 31, and an auxiliary fastener 34 for tightening the auxiliary member body 31 so as to narrow the width of the auxiliary split groove 33. The auxiliary member body 31 is made of an aluminum alloy. The auxiliary member body 31 is a rectangular parallelepiped. More specifically, a pair of opposing faces of the auxiliary member body 31 are rectangular in shape with adjacent sides having slightly different lengths, and these two faces are called end faces 31a. The end faces 31a are vertical faces, with the horizontal sides being short sides and the vertical sides being long sides. The length of the short sides is the same as the length of the sides of the end faces 21a of the central member body 21. Four faces perpendicular to the end face 31a are rectangular (two faces are square), and the length of the side perpendicular to the end face 31a is the same as the length of the short side of the end face 31a. These four faces are called side faces 31b. The auxiliary through hole 32 penetrates from one end face 31a to the other end face 31a of the auxiliary member main body 31. The auxiliary through hole 32 has a circular cross section, and its diameter is large enough to fit the bar 200. The center of the auxiliary through hole 32 is slightly shifted downward (to one short side) from the center of the end face 31a. The auxiliary split groove 33 is formed on the upper side face 31b of the auxiliary member main body 31. The upper side face 31b is the side face 31b that contacts the other short side of the end face 31a (the short side away from the auxiliary through hole 32). The auxiliary split groove 33 extends from the center of the side of the side face 31b on one end face 31a side to the center of the side of the other end face 31a side. The auxiliary dividing groove 33 penetrates in the vertical direction from the surface of the side surface 31b to the auxiliary through hole 32. In addition, a protrusion 39 is formed along both edges of the auxiliary dividing groove 33 on the upper side surface 31b on which the auxiliary dividing groove 33 is formed. The protrusion 39 extends from one end surface 31a side to the other end surface 31a side. The width of one protrusion 39 is approximately 1 / 4 of the width of the side surface 31b. Two bolt holes 35 are formed side by side in the horizontal direction on the side surface 39b of the protrusion 39 (a surface parallel to the vertical side surface 31b of the auxiliary member main body 31). Two recessed grooves 39a having a semicircular cross section are formed on the upper side surface 31b perpendicular to the side surface 39b of the protrusion 39.The recessed groove 39a corresponds to the position of the bolt hole 35, and the lower half of the bolt hole 35 opens toward the recessed groove 39a. The bolt hole 35 extends horizontally, penetrates the auxiliary member body 31, and opens into the auxiliary split groove 33. Furthermore, two female screw holes 36 are formed on the surface of the auxiliary split groove 33 that faces the surface where each bolt hole 35 opens. The female screw holes 36 face the bolt holes 35, respectively. The female screw holes 36 extend horizontally and penetrate to the side surface 39b of the protrusion 39. The auxiliary fastener 34 is made of two bolts. When the auxiliary fastener 34 is inserted into the bolt hole 35, the tip of the auxiliary fastener 34 screws into the female screw hole 36. By screwing the auxiliary fastener 34 with the head engaged with the side surface 39b of the protrusion 39, the auxiliary member body 31 is tightened so as to narrow the width of the auxiliary split groove 33. Therefore, when the auxiliary fastener 34 is screwed in with the bar 200 inserted in the auxiliary through hole 32, the bar 200 is tightened to the auxiliary member body 31, and the bar 200 is fixed to the auxiliary member body 31. Bolt holes 37 are formed in the four corners of the end face 31a.

[0025] The auxiliary member 30 is attached to the central member body 21. When the end face 31a of the auxiliary member body 31 is abutted against the end face 21a of the central member body 21, the female screw hole 27 of the central member body 21 and the bolt hole 37 of the auxiliary member body 31 communicate with each other. The auxiliary member body 31 is fixed to the central member body 21 by inserting a bolt 37a into the bolt hole 37 of the end face 31a of the central member body 21 opposite to the auxiliary member body 31 side and screwing it into the female screw hole 27. The end face 21a of the central member body 21 and the end face 31a of the auxiliary member body 31 have approximately the same shape, and by fixing as described above, each side face 21b of the central member body 21 and each side face 31b of the auxiliary member body 31 become approximately flush with each other. In addition, the center through hole 22 of the central member body 21 communicates with the auxiliary through hole 32 of the auxiliary member body 31. The auxiliary member 30 is attached to both end faces 21a of the central member body 21.

[0026] Three rods 200 are connected to the connector 100 thus configured, forming a structure 300 of the present invention. As shown in FIG. 4, the rods 200 have the same length, and the central portion of each rod 200 is fixed to the connector 100. More specifically, the rods 200 are inserted into the end through-holes 12 of the end members 10, and are fastened by the fasteners 14 to fix the rods 200 to the end member body 11. The rods 200 are also inserted into the center through-holes 22 of the middle member 20 and the auxiliary through-holes 32 of the auxiliary member 30, and are fastened by the auxiliary fasteners 34 to fix the rods 200 to the auxiliary member body 31. Since the auxiliary member body 31 is fixed to the middle member body 21, the rods 200 are fixed to the middle member body 21. In the structure 300 thus configured, the three rods 200 cross each other vertically at the point where the connector 100 is located. The extending directions of the bars 200 differ from each other by 60 degrees when viewed from above.

[0027] Furthermore, the flying object 400 of the present invention is configured with the structure 300 configured as above as the airframe. As shown in FIG. 5, the flying object 400 includes the structure 300 as the airframe, rotors 401, legs 402, and other equipment 403. The rotors 401 are provided at both ends of each of the rods 200. That is, the flying object 400 includes six rotors 401. The legs 402 include six vertical support legs 404 and horizontal beams 405. The upper ends of the support legs 404 are connected to the ends of the respective rods 200 and the middle part of the connector 100. The beams 405 are horizontally supported by the adjacent support legs 404 at a height position midway between the support legs 404 in the vertical direction. The equipment 403 includes various parts necessary for flight, such as a control device, a communication device, and a battery. The equipment 403 is, for example, housed inside a space formed by six support legs 404. The equipment 403 and the rotor 401 are connected by wiring (not shown). In this case, holes may be drilled in the bar 200 at locations corresponding to the communication holes 18, 28 of the connector 100, and the wiring may be connected to the rotor 401 from the communication holes 18, 28 through the inside of the bar 200. The above-mentioned components and other components may be fixed to the connector 100 by using the female screw hole 17 of the end member 10 of the connector 100. Other components may include hooks for suspending cargo, and tanks and nozzles for spraying liquids or granules.

[0028] According to the connector 100 of the present invention, a structure 300 can be formed in which a plurality of rods 200 extend horizontally from the connector 100. The rods 200 penetrate the connector 100 and can extend on both sides, so that the rods 200 extend in a direction twice as long as the number of rods 200, starting from the connector 100. The structure is such that the rods 200 penetrate and are fixed to the end member body 11 and the central member body 21, which are integrated, respectively, so that the structure is strong. In addition, the structure is such that each rod 200 extends from one end of the structure 300 to the other end without being cut, so that the structure is also strong. Furthermore, in the end member 10, the rods 200 inserted into the end through holes 12 are fastened and fixed by the fasteners 14, and in the auxiliary member 30, the rods 200 inserted into the auxiliary through holes 32 are fastened and fixed by the auxiliary fasteners 34, so that the structure is particularly strong and easy to fix. The auxiliary members 30 provide high strength and ease of fixing of the bar 200 penetrating the central member 20 having no split groove. Because the auxiliary members 30 are attached to both sides of the central member body 21, the bar 200 can be fixed more reliably to the central member 20 compared to, for example, a case in which the auxiliary members 30 are attached only to one side of the central member body 21. Furthermore, because multiple bar materials 200 can be connected with one connector 100, it is lightweight.

[0029] The structure 300 formed by the connector 100 and the rods 200 of the present invention is strong and lightweight as described above. In addition, by connecting three rods 200 of the same length that extend in directions that differ by 60 degrees from each other when viewed from above, a structure 300 can be formed in which the ends of the rods 200 are located at the vertices of a regular hexagon when viewed from above. Such a strong and lightweight structure 300 is suitable as the body of an aircraft 400, and contributes to extending the flight time (range) of the aircraft.

[0030] Next, the connector 100a of the second embodiment will be described. As shown in FIG. 6, the connector 100a of the second embodiment includes two end members 10, two middle members 20, and four auxiliary members 30 (auxiliary members 30 are omitted). The shapes of the end members 10, the middle members 20, and the auxiliary members 30 are the same as those of the first embodiment, so their description will be omitted. In the connector 100a of the second embodiment, two middle members 20 are sandwiched between two end members 10 positioned above and below. That is, the shape is four rectangular parallelepipeds stacked on top of each other. The longitudinal direction of the upper end member 10 coincides with the front-rear direction. The longitudinal direction of the upper middle member 20 coincides with the direction rotated 45 degrees clockwise from the front-rear direction when viewed from above. The longitudinal direction of the lower middle member 20 coincides with the direction rotated 90 degrees from the front-rear direction (left-right direction) when viewed from above. The longitudinal direction of the lower end member 10 coincides with a direction rotated 45 degrees counterclockwise with respect to the front-rear direction in a top view. That is, the end through-holes 12 of the two end members 10 and the center through-holes 22 of the two center members 20 extend in directions that differ by 45 degrees each. According to the connector 100a of the second embodiment, for example, by connecting four rods 200 of the same length, a structure 300 can be formed in which the ends of the rods 200 are located at the vertices of a regular octagon in a top view.

[0031] Next, a third embodiment of the connector 100b will be described. As shown in FIG. 7, the connector 100b of the third embodiment includes two end members 10, two middle members 20, and four auxiliary members 30 (auxiliary members 30 are omitted). The shapes of the end members 10, the middle members 20, and the auxiliary members 30 are the same as those of the first embodiment, so their description will be omitted. In the connector 100b of the third embodiment, two middle members 20 are sandwiched between two end members 10 located above and below. That is, the shape is four cuboids stacked on top of each other. The longitudinal direction of the upper end member 10 and the lower middle member 20 coincides with the front-rear direction. The longitudinal direction of the upper middle member 20 and the lower end member 10 coincides with the direction rotated 90 degrees from the front-rear direction (left-right direction) when viewed from above. That is, the extension directions of the end through holes 12 of one set of end members 10 and the central through holes 22 of the central member 20 differ by 90 degrees from those of the other set of end through holes 12 of end members 10 and the central through holes 22 of the central member 20. According to the connector 100b of the third embodiment, for example, by connecting four rods 200 of the same length, it is possible to configure a structure 300 in which the ends of the rods 200 form pairs one above the other and are located at the vertices of a square when viewed from above.

[0032] The couplers 100a, 100b of the second and third embodiments have the same advantages as the coupler 100 of the first embodiment.

[0033] The present invention is not limited to the above-mentioned embodiment, and the shape and structure of each part can be appropriately changed within the scope of the invention, taking into consideration the application target and design. For example, the shape of the end member, the middle member and the auxiliary member may be any shape other than a rectangular parallelepiped. The cross section of the rod may be a shape other than a circle. In that case, the end through hole, the middle through hole and the auxiliary through hole also have a corresponding shape. In addition, when fixing the rod to the end member body or the auxiliary member body, a key may be inserted between the end member body or the auxiliary member body and the rod, or a tape for preventing slipping may be wrapped around the rod. Furthermore, in the flying object, the rod may be structured to be foldable. [Explanation of symbols]

[0034] 10 End member 11 End member body 12 End through hole 13 Warizo 14 Fasteners 20 Inner material 21 Main body of inner part 22 Medium through hole 30 Auxiliary Materials 31 Auxiliary member body 32 Auxiliary through hole 33 Auxiliary split groove 34 Auxiliary fasteners 100,100a,100b Connector 200 Bar material 300 structures 400 Flying Objects 401 Rotor

Claims

1. A connector for connecting three or more rods each extending horizontally, The rod member is attached to each of two end members and one or more middle members, and an auxiliary member. the end member has an end member body, an end through hole that penetrates the end member body in a horizontal direction and into which the bar is inserted, a split groove that is formed in the end member body and connects the end through hole to the outside of the end member body, and a fastener that tightens the end member body so as to narrow the width of the split groove; The central member has a central member body and a central through hole that penetrates the central member body in a horizontal direction and into which the bar is inserted, The middle member is sandwiched between the two end members located above and below, and the end member body and the middle member body are integrated together, A connector characterized in that the auxiliary member fixes the rod material to the central member body.

2. The auxiliary member is attached to the inner member body, 2. The connector according to claim 1, further comprising: an auxiliary member body; an auxiliary through hole that penetrates the auxiliary member body horizontally and into which the rod is inserted; an auxiliary split groove that is formed in the auxiliary member body and connects the auxiliary through hole to the outside of the auxiliary member body; and an auxiliary fastener that tightens the auxiliary member body so as to narrow the width of the auxiliary split groove.

3. 3. The connector according to claim 2, wherein the auxiliary members are attached to the respective faces of the inner member body where both ends of the inner through hole are open.

4. A connector for connecting three of the rods, The present invention provides a method for manufacturing a casing having a single central member, 4. The connector according to claim 3, wherein the extending directions of the rods differ from each other by 60 degrees when viewed from above.

5. A connector according to claim 1, 2, 3 or 4, and the rod material, The bar is inserted into the end through-hole of the end member and fastened by the fastener to fix the bar to the end member body, A structure characterized in that the bar material is inserted into the central through hole of the central member, and the bar material is fixed to the central member body by the auxiliary member.

6. 6. An aircraft comprising the structure according to claim 5, and rotors provided at both ends of each of said rods.

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